Ultrasonic agitator

Abstract

An ultrasonic agitator (10) for generating turbulence in the vicinity of elongated metal workpieces (12) such as newly formed strands of wire. The system includes a bath (14) that is filled with a cleaning solution (16). The workpiece is introduced into the bath so as to move along a predetermined path of travel. One or more transducers (20, 24) are disposed in the bath to produce ultrasonic waves in the cleaning solution. The transducers are further configured and spaced so that the focal points of the vibrations substantially coincide with the path of travel with the workpiece. The transducers are driven by a signal generator (28) that causes the transducers to vibrate at a frequency between 0.5 and 3.0 MHz. The vibrations of the transducers produce ultrasonic waves that can be used to scrub off contaminants from the surface of the workpiece.

We claim: 
     
       1. An ultrasonic agitator for exposing a workpiece to a turbulent fluid flow, including: a first bath in which the workpiece is disposed at a selected location;   a fluid adapted to be disposed in said first bath, wherein in operation of the agitator, the workpiece is immersed in said fluid;   a transducer connected to said first bath so as to be in mechanical communication with said fluid, said transducer being configured to produce ultrasonic waves in said fluid and shaped and positioned so as to produce converging waves in said fluid that converge at a focal point that substantially coincides with said selected location at which the workpiece is positioned; and   a transducer drive system connected to said transducer for causing said transducer to vibrate at a frequency of at least 500 kHz so that said drive system causes the formation of waves that converge at said selected location at which the workpiece is located so as to produce a turbulent fluid flow adjacent the workpiece.   
     
     
       2. The ultrasonic agitator of claim 1, wherein said fluid is an electroplating liquor, and wherein the agitator includes means for creating a potential between the workpiece and an electrode so as to electroplate the workpiece. 
     
     
       3. The ultrasonic agitator of claim 1, wherein said solution is an electrolytic solution, and wherein the agitator includes means for creating a potential between the workpiece and an electrode so as to electropickle the workpiece. 
     
     
       4. The ultrasonic agitator of claim 1, wherein the workpiece is in the form of an elongated member having a longitudinal axis and said transducer is in the form of an elongated member having a longitudinal axis with a laterally extending cross-section profile so that said waves produced in said fluid converge along a focal line. 
     
     
       5. The ultrasonic agitator of claim 1, wherein: said first bath is an overflow bath, said overflow bath having a pair of end walls, said end walls being formed with indentations through which the workpiece is introduced into and removed from said overflow bath, said end walls being shaped so that the workpiece is introduced into and removed from said overflow bath without substantially contacting said end walls, and said agitator further includes:   a second, collecting bath located below said overflow bath and positioned to receive said fluid drained from said overflow bath; and   a pumping system connected between said collecting bath and said overflow bath for returning said fluid from said collecting bath to said overflow bath, said pumping system having a discharge port positioned to discharge said fluid so that said workpiece is immersed in said fluid.   
     
     
       6. The ultrasonic agitator of claim 1, wherein the workpiece is in the form of an elongated member that moves along a path of travel through said first bath, and said transducer is in the form of an elongated member that produces ultrasonic waves in said fluid that converge along a focal line, and said transducer is secured to said first bath so that the focal line of said waves substantially coincides with said path of travel of the workpiece. 
     
     
       7. The ultrasonic agitator of claim 6, wherein said transducer drive system vibrates said transducer at a frequency between 500 kHz and 3 Mhz. 
     
     
       8. The ultrasonic agitator of claim 1, wherein the workpiece is in the form of an elongated member that moves along a path of travel through said fluid, and said agitator further includes a plurality of transducers, said transducers being of the type that produce ultrasonic waves in said fluid that converge on a focal point, and said transducers are secured to said first bath so that the focal points of said waves substantially coincide with said path of travel of the workpiece. 
     
     
       9. The ultrasonic agitator of claim 8, wherein said transducers are positioned so that the focal points of said waves coincide with spaced-apart points along said path of travel of the workpiece. 
     
     
       10. The ultrasonic agitator of claim 8, wherein said transducer drive system vibrates said transducers at a frequency between 500 kHz and 3 MHz. 
     
     
       11. An ultrasonic agitator for exposing a workpiece to a turbulent fluid flow, said workpiece moving along a preestablished path of travel, said agitator including: an overflow bath, said overflow bath having a pair of end walls, said end walls being formed with openings through which the workpiece is introduced into and removed from said overflow bath when the workpiece is moved along the path of travel, said end walls being shaped so that the workpiece moves along the path of travel without substantially contacting said end walls;   a fluid adapted to be disposed in said overflow bath, said fluid being of a sufficient volume to substantially immerse the workpiece and flow out of said overflow bath through said end wall openings;   at least one transducer secured to said overflow bath to ultrasonically vibrate said fluid therein;   a collecting bath located below said overflow bath and positioned to receive said fluid that flows out of end wall openings of said overflow bath; and   a pumping system connected between said collecting bath and said overflow bath for returning said fluid from said collecting bath to said overflow bath, said pumping system having a discharge port positioned to discharge said fluid so as to continually immerse the workpiece in said fluid.   
     
     
       12. The ultrasonic agitator of claim 11, wherein said end walls of said overflow bath are shaped to define open-ended openings. 
     
     
       13. A method of subjecting an elongated metal workpiece to a turbulent fluid flow, including the steps of: immersing the workpiece in a fluid, moving the workpiece through said fluid along a preselected path of travel, and removing the workpiece from said fluid; and   generating ultrasonic waves in said fluid as the workpiece travels through said fluid, said ultrasonic waves being generated so as to converge toward at least one point along said workpiece path of travel and being generated to have a frequency of at least 500 kHz so that said waves induce a turbulent fluid flow in said fluid adjacent the workpiece.   
     
     
       14. The method of claim 13, wherein said ultrasonic waves are generated at two locations in said bath and are generated so as to converge at least two separate focal points in said bath, each said focal point being at a location that substantially corresponds to said path of travel of the workpiece. 
     
     
       15. The method of claim 13, wherein said fluid is an electrolytic solution, and further including the step of creating a potential between the workpiece and an electrode in contact with said electrolytic solution so as to electropickle the workpiece. 
     
     
       16. The method of claim 13, wherein said fluid is an electroplating liquor, and further including the step of creating a potential between the workpiece and an electrode in said electroplating liquor so as to electroplate the workpiece. 
     
     
       17. The method of claim 13, wherein said fluid is a solution for cleaning the workpiece, and the ultrasonic waves produce a cleaning of the workpiece. 
     
     
       18. An ultrasonic agitator for exposing a workpiece to a turbulent fluid flow, including: an overflow bath having a pair of end walls, said end walls being formed with at least one indentation through which the workpiece is introduced into and removed from said overflow bath, said end wall being shaped so that said workpiece is introduced into and removed from said overflow bath without substantially contacting said end walls;   a fluid adapted for disposal in said overflow bath, wherein in operation of the agitator, the workpiece is immersed in said fluid;   a collecting bath located below said overflow bath and positioned to receive said fluid drained from said overflow bath;   a transducer connected to said overflow bath so as to be in mechanical communication with said fluid, said transducer being configured to produce ultrasonic waves in said fluid;   a transducer drive system connected to said transducer to vibrate said transducer; and   a pumping system connected between said collecting bath and said overflow bath for returning said fluid from said collecting bath to said overflow bath, said pumping system having a discharge port positioned to discharge said fluid into said overflow bath so that said workpiece is immersed in said fluid.   
     
     
       19. The ultrasonic agitator of claim 18, wherein said overflow bath end walls are formed with a first indentation through which the workpiece is introduced into said overflow bath and a second indentation through which the workpiece is removed from the overflow bath. 
     
     
       20. The ultrasonic agitator of claim 18, wherein the workpiece is in the form of an elongated member that moves along a path of travel through said overflow bath, and said transducer is in the form of an elongated member that produces ultrasonic waves in said fluid that converge along a focal line, and said transducer is secured to said first bath so that the focal line of said waves substantially coincides with said path of travel of the workpiece. 
     
     
       21. The ultrasonic agitator of claim 18, wherein the workpiece is in the form of an elongated member that moves along a path of travel through said fluid, and said agitator further includes a plurality of transducers, said transducers being of the type that produce ultrasonic waves in said fluid that converge on a focal point, and said transducers are secured to said first bath so that the focal points of said waves substantially coincide with said path of travel of the workpiece. 
     
     
       22. A method of subjecting an elongated metal workpiece to a turbulent fluid flow, including the steps of: immersing the workpiece in an electrolytic solution, moving the workpiece through said solution along a preselected path of travel, and removing the workpiece from the solution;   generating ultrasonic waves in said electrolytic solution as the workpiece travels through said solution, said ultrasonic waves being generated so as to converge toward at least one point along said workpiece path of travel and further being generated to have a frequency of at least 500 kHz; and   creating a potential between the workpiece and an electrode in contact with said electrolytic solution so as to electropickle the workpiece.   
     
     
       23. A method of subjecting an elongated metal workpiece to a turbulent fluid flow, including the steps of: immersing the workpiece in an electroplating liquor, moving the workpiece through said electroplating liquor along a preselected path of travel, and removing the workpiece from the electroplating liquor;   generating ultrasonic waves in said electroplating liquor as the workpiece travels through said solution, said ultrasonic waves being generated so as to converge toward at least one point along said workpiece path of travel and further being generated to have a frequency of at least 500 kHz; and   creating a potential between the workpiece and an electrode in contact with said electroplating liquor so as to electroplate the workpiece.